Óptica geométrica e ondas · GCSE Physics Topic 6
Simulador de refração de Snell e reflexão total
Simulador da lei de refração de Snell e reflexão interna total: refração na água
- No navegador
- Sem cadastro
- Dedução ao vivo
- Modo projetor
- Folha de exercícios A4
Janela de simulação 3D● 60 FPS
Variáveis de controle do experimento
°
m
Deduções e métricas em tempo real
Ângulo de refração θ2
--
Ângulo crítico θc
--
Profundidade aparente
--
Fenômeno de RIT
--
Dedução de fórmulas em tempo real
Fórmula fundamental:
--Substituição de valores:
--Estado físico: --
Exemplos clássicos e armadilhas de exame
Worked Problem
Problema: Light enters glass (n=1.414) at 45° from air. Find angle of refraction and critical angle.
Derivação passo a passo:
- 1.0*sin(45°) = 1.414*sin(θ2) => sin(θ2) = 0.5 => θ2 = 30°. Critical angle sin(θc) = 1/1.414 => θc = 45°.
Worked Problem
Problema: A pool is 2m deep (n=1.333). Viewed from directly above, what is the apparent depth of the bottom?
Derivação passo a passo:
- Apparent depth h_app = h_real / n = 2 / 1.333 ≈ 1.5m. The pool appears 0.5m shallower than it is.
Folha de investigação em aula e exercícios
Q1. Variant 1: Viewed by a scuba diver looking up from water, do shore trees appear taller or shorter?
Answer Key: Taller! Light refracts toward normal entering water. Diver's back-projected sightline places tree tops higher.
Q2. Variant 2: What two conditions are necessary for total internal reflection? How does fiber optics utilize it?
Answer Key: 1) From denser to rarer medium (n1 > n2); 2) incident angle exceeds critical angle. Fiber core n > cladding n keeps light trapped inside.
Q3. Variant 3: Light traverses a flat glass slab. What happens to the exiting ray compared to the incident ray?
Answer Key: The exiting ray remains strictly parallel to the incident ray, experiencing only a lateral parallel displacement.
Perguntas frequentes e erros comuns
Why does a spear require aiming below the fish while a laser needs direct aim?
Spear travels in a straight line unaffected by refraction. Laser is light, and by reversibility of light, refracts along the identical path back to the real fish.
Why do hot asphalt roads appear to have water puddles in the distance in summer?
Inferior mirage. Blistering tarmac heats surface air, lowering refractive index. Downward skylight undergoes total internal refraction, creating illusory reflections.
Why do diamonds sparkle far more brilliantly than glass gemstones?
Diamonds have a high refractive index (n=2.42) and small critical angle (24.4°). Light undergoes multiple total internal reflections before exiting.
Why does a chopstick submerged in water appear bent upward at the surface?
Light from the submerged section bends away from normal upon exiting water. Apparent depth is shallower, making the stick look bent.